Metal-working machine



Dec. 1,1953 G. E. HIEBER 2,660,738

METAL-WORKING MACHINE Filed Oct. 15, 1947 1O Sheets-Sheet l awe/WM GEORGE E. HIEBER MAN KW Dec. 1, 1953 G. E. HIEBER METAL-WORKING MACHINE 10 Sheets-Sheet 2 Filed Oct. 15, 194'? GEORGE E. HIEBER k J N Dec. 1, 1953 G. E. WEBER 2,660 736 METAL-WORKING MACHINE Filed Oct. 15, 1947 10 Sheets-Sheet 4 JJ :22 300 166% 8 6 153 F 152 L 6 3 o 5 SOGILI 308 I gwovm bw 66 I 5 74 GEORGE E. HIEBER Dec. 1, 1953 G. E. HIEBER 2,660,738

METAL-WORKING MACHINE Filed Oct. 15, 1947 10 Sheets-Sheet 5 294 2 7 FT 9 5 2 g; 272 268 278 E57 GEORGE E. HIEBER mskxw M 1953 G. E. HIEBER 2,660,738

METAL-WORKING MACHINE Filed Oct. 15, 1947 10 Sheets-Sheet a GEORGE E. HIEBER Dec. 1, 1953 G. E. HIEBER 2,660,738

METAL-WORKING MACHINE Filed 001. 15, 1947 10 Sheets-Sheet 1o GEORGE E. HIEBER mmm &

Patented Dec. 1, 1953 UNITED STATES FA'E'ENT OFFICE METAL-WORKING MACHINE George E. Hieber, Waynesboro, Pa., assignor to Landis Machine Company, Waynesboro, Pa., a corporation of Pennsylvania Application October 15, 1947, Serial No. 779,926

11 Claims.

This invention relates to metal Working machines and more particularly to a machine for the tapping of pipe couplings and the like.

An object of this invention is the provision of an improved semi-automatic machine for tapping couplings and the like which will achieve the maximum production of accurately threaded articles at a minimum cost.

Another object of the invention is to provide hydraulic operation for all heavy mechanisms of the machine, thus reducing operator fatigue.

A further object is to provide a machine wherein the controls for such hydraulic operation are interlocked to prevent their actuation except in proper timed sequence.

Another object of the invention is to provide a coupling tapping machine in which a replaceable leadscrew is coaxial with the tapping spindle thus eliminating the usual gearing between these elements.

A further object is to provide a work locating mechanism which is adjustable in infinitely small increments within a given range of coupling lengths and thread lengths and which will also facilitate the loadingv and unloading of heavy couplings.

Still another object is to provide improved automatic means for performing various of the operations in the working cycle such as stopping the tap on its approach to the work, disengaging the lead screw nuts, resetting the tap, etc.

The machine described in this specification is intended for use upon the larger sizes of pipe couplings and is therefore of rugged construction and many of the moving parts are necessarily heavy. Hence hydraulic or other fluid means oi operation is most desirable. At the same time. fully automatic operation is undesirable. The necessary controls and other automatic mechanisms add greatly to the first cost of such a machine and do not appreciably improve the quantity of production thereof. For example, in the present invention, the leadscrew nuts are engaged upon the leadscrew manually, thus eliminating the complex and expensive timer mechanism employed when such engagement is accomplished by hydraulic or other automatic means. Moreover, there is no difference in the time required to accomplish this operation whether by manual or automatic means.

Nor is the operator constantly tied to one machine. On the larger sizes of couplings, the time required for the actual tapping may be or 10 minutes out of a total cycle time of approximately 12 minutes. During the actual thread cutting operation, the tap is driven by the lead screw and the operators attention is not required for this large portion of the cycle time. Such time may then be used for loading and starting the threading cycle on other machines.

For the above reasons, the machine is largely hand controlled and hydraulically operated with certain necessary automatic mechanisms, although methods of rendering the machine fully automatic will readily suggest themselves to those skilled in the art.

In the accompanying drawings there is shown for purposes of illustration a preferred embodiment of the present invention, it being understood that the drawings do not define the limits of the invention as changes in the construction and operation disclosed therein may be made without departing either from the spirit of the invention or scope of the claims.

In the drawings:

Figure l'is a front elevation of the entire machine;

Figure 2 is a horizontal sectional View of the machine taken substantially on line 2-2 of Figline 4-4 of Figure 3;

Figure 5 is a fragmentary sectional view taken on line 5-5 of Figure 4;

Figure 6 is a fragmentary sectional view taken on line E6 of Figure 3;

Figure 7 is a fragmentary sectional view taken on line 'l---? of Figure 6;

Figure 7a is a detail plan view of certain of the parts shown in Figure '7.

Figure 8 is a fragmentary sectional view taken on line 8-8 of Figure 6;

Figure 9 is a front elevation of machine, partially in section;

Figure 10 is a plan view of the work-holding chuck and associated parts partially in section;

Figure 11 is a vertical sectional view taken on line I I-H of Figure 10 and showing the chuck in threading position;

Figure 12 is a front elevation of the base portion of the machine, partially in section and showing the chuck and locating device in loading position;

Figure 13 is a fragmentary sectional view taken substantially on line [3-43 of Figure 12;

Figure 1a is a fragmentary sectional view taken substantially on line i l-M of Figure 10;

a part of the Figure 15 is a fragmentary sectional view taken on line I5l5 of Figure Figure 16 is a fragmentary sectional view taken substantially on line Iii-I5 of Figure 12;

Figure 17 is a fragmentary sectional view taken substantially on line I?-I'l of Figure 12;

Figure 18 is a fragmentary vertical transverse section showing the operation of one of the control valves by the carriage;

Figure 19 is a fragmentary sectional view taken on line Iii-4Q of Figure 2;

Figure 20 is a fragmentary sectional view taken on line 29-20 of Figure 2;

Figure 21 is a fragmentary sectional view taken on line 2 I2! of Figure 20;

Figure 22 is a detail elevation of the cams for controlling rapid traverse 01 the tap;

Figure 23 is a fragmentary sectional view taken on line 23-23 of Figure 22;

Figure 2a is a detail elevation of the cam controlling disengagement of the leadscrew nuts; and

Figure 25 is a diagram of the hydraulic control circuit.

The machine comprises a base ll] (Figure 1) supporting, on opposite sides a pair of columns 42 and 54. An arch 46 is mounted on the upper ends of columns 42, M thus forming a substantially rectangular space in the center of the machine wherein is mounted in a manner later to be described, a gear box it which supports the tool or tap 56.

Any collapsible, taper producing tap may be used with the machine. The tap 50 shown in the drawings is shown and described in United States Patent No. 2,291,744, issued to Frederic Nell.

The collapsible tap 59 is removably secured to a spindle 52 as shown in Figures 3 and 4. The rear end of the tan is provided with an adapt element 5 3 which is secured to a body member 5K5 of the tap by screws, 58. To ensure concentricity between tap 5B and spindle 52. adapter 54 is provided with a rear flanged portion 69 which is received in a corresponding recess in an attaching-flange 62. To further secure the tap 5D to flange 62, the body 56 isv provided with a rear flanged portion 64 to which flange 62 is secured by screws 66.

Concentricity between flange 62 and spindle E2 is obtained by providing flange 62 with a rear boss portion as which is received in a corresponding recess in the lower end of spindle 52. Flange E2 is further secured to the lower flanged end of spindle 52 by means of the screws 16.

The lower end of spindle 52 is journalled for rotation in a suitable anti-friction bearing '52 which is contained in a bearing housing It. A plurality of screws I5 are employed to secure bearing housing It in an opening in the bottom wall of gear box ea. As shown in Figure .3, gear box 48 is provided with a topcover in two sections I8 and 8B, which are secured to gear box 48 by screws BI. Cover section I8 supports in an opening therein a second anti-friction bearing 82 through which the reduced-diameter upper end of spindle 52 is journalled for rotation. Spindle 52 and tap 50 are secured in correct axial position in gear box 48 by means of lock nuts as threadedly engaged upon the upper extremity of spindle 52 and abutting bearing 82.

Reference to Figure 2 will show that gear box 48 is provided, along the sides thereof, with vertically extending guideways 86 and 8B which are adapted to engage vertical guides 95 and 92 formed along the inwardly facing walls of columns t2 and M, respectively. Thus free linear movement of gear box it and all parts attached thereto, in a vertical direction, is permitted. Guideways 86 and 88 may be provided with hardened wear strips as is well understood in the art. Wiper members 9 3 and 96 may also be secured by screws 58 to both ends of guideways 86 and 88 to prevent the entrance of foreign matter between the relatively sliding surfaces.

As shown in Figure 3, cover member I3 is provided with a counterbored opening Hit in which a nut. member Hi2 is seated. Nut iii? is retained. in opening Iilii by a plate its and screws Hit. The piston rod Iill of a hydraulic cylinder I33 is threadedly engaged in nut I62 while said cylinder I98 is secured by screws Iii to the interior of the. forward wall of arch d3. Nut its on rod Iii? threaded against plate its prevents relative rotation between the piston rod and nut Hi2. Therefore it will be seen that gear box d8 may be moved vertically on guides at and s2 by the action of cylinder E98.

,An electric motori I2 is secured in the con ventional manner to the underside of the rear portionof gear box 33 as shown and is employed to drive a worm Iii through a series of changespeed gears and clutch (not shown). Worm Ila in constant mesh with a worm gear I it which is secured by bolts H8 to a hub I26. ,Hub IE8 is mounted on a tapered portion of spindle and is retained in position axially by a lock nut 522 which is threadedly engaged on spindle upwardly adjacent hub 12%. A hey its provides a means whereby spindle maybe drivenby worm gear I It. t should be noted that hearing housing is is provided with an integral upward extension I26 which surrounds a portion of hub $20 to prevent escape of lubricant contained the lower portion of gear box 28.

As shown in Figures 3 and 9, a pair of beaded pins I28 are mounted in the gear box cover pl ?8 and are attached at their upper ends to cha I39 each of which passes over spaced spro 32. The rear wall of arch se is provided w bosses 13d (Figure 3) to receive sprocket stud I39. Anti-friction bearings I38 are mounted on studs I33 onthe interior of the wall of arch and carry the. sprockets I32. Lock nuts HEB are engaged upon the forward ends of studs 36 to retain bearings I 58 in axial position.

After engaging sprockets chains 539 e:- tend downwardly into the respective columns and Eli where each is secured to a counterweight I42 by means of a pin Md. The total weight of counterwoights 562 should only slightly overbalance the total weight of gear box Q3, tap 5.,- and motor I i2 so that the work required to move the gear box, etc, will be reduced nearly to zero.

Referring to Figures 4 and 5, the in rior of the upper end of spindle is tapered rdly and outwardly to receive a complementary tapered end of a spindle extension member Mt. A tubular leadscrew MS is mounted upon the upper rcduced-diameter portion of extension member its and its lower interiorly tapered end engages conical shoulder 553 on member The interior of the upper end or" leadscrew hit is also formed conically to receive a frusto-conical bushing I52. A nut E53 is threadedly engaged upon the upper extremity of extension i ii to produce a wedging action between bushing 552 and shoulder I50 and thereby retain lea'dscrew M8 in position on extension I 35. A tube I54 is threadeclly engaged in the interior of the lower end of extension M6 and extends downwardly inside spindle 52 to engage similarly a support member I55.

hus tube acts as a drawbar to hold member its against shoulder Hit in the interior of spindle and to hold extension Mt rigidly in its seat in the top of said spindle.

A key is secured in a recess in the top end of spindle by screw it? and extends into keyway let in extension Hi6 thus insuring unitary rotary movement of these parts. A key I66 is secured to extension M25 to engage a slot in the lower end of leadscrew his and thus provide for the unitary rotation of extension Hi5 and lead screw Extension 55% is provided at its upper end with a recess to receive a bushing 53. A rod ll'il is journalled through bushing its and extends downwardly through the interior of extension itli and tube A plate H2 is threadedly engaged on the lower end of rod H and is located between support in I58 and flanged portion or" adapter element 54 for axial movement in boss on flange 62. Relative rotation between pie a iii? rod Hill is prevented. by a radially dheoted set screw I'l threaded into plate iii. and engaging the threaded end of rod lit. One or more pins I'IS are frictionally mounted in. plate H2 and extend downwardly therefrom through suitable openings in adapter member 55 toward the rear end of tap sleeve member H8.

The tap mechanism is reset after a tapping operation by means of a mechanism comprising a blocl: idil which is secured near the top of the forward wall of arch as by screws 182 (Figure t). A shaft is disposed transversely through block Hit. A bell crank ass is rocka'oly mountec on shaft its adjacent one side of block ltd and the headed end oi shaft iB l together with set screw ii -Si in block 283 retains bell crank ice in correct axial position. One arm of bell crank i8 extends outwarchy so as to be positioned directly over the upper end of rod iii A set screw Mill is threaded through this arm of crank use and is adjustably retained in position by nut Hi2. Therefore, it is evident that, when gear box 58 and the parts associated therewith are at the tap of thei path of travel as shown in Figures 3 or We engages the top end of rod H9. or end of crank see extends downwardly and is provided with a rectangular recess in the end thereof to engage a portion of a pin led, This pin 59 i is iriotionally fitted transversely througl'i a stud, Hit; (Figure 5) which is non rotsly mounted in the bore of a bracket 598. .Is 2%: attach bracket 593 to the for ward of arch downwardly adjacent to block sea. A 510 2832 is provided. in the side of t bracket the rroit a limited amount of movement of pi J. s and consequently a limited amount of axial movement of stud E96.

Stud till? e...tends rearwardly through the wall of arch ii} and on its threaded rearward end a washer 23 i and nut 29s.": are mounted. A spring ass surroui ng stud i955 is adjustably held in compression between. washer 2% and the rear face of bracket E98. Thus, it is seen that the action of 29% constantly urges pin 5% rearwardly set screw i853 downwardly. When screw i-iii engages the top end of rod Hi5, therefore, the force of spring 2&8 is transxnitte through rod i'it to force pin ilt downwardly against tap sleeve member lit. As shown in the above mentioned Nell patent, such pressure against sleeve I18 results in the tap being reset to begin a threading operation.

A collar 2:0 is pinned to rod i'iii and a spring M2 is retained in compression between collar 250 and the upper end of tube i5 2. Therefore, when the tap 50 and rod Ht are moved downwardly out of contact with the ta closing mechanism, the force of spring 222 is exerted to lift rod Hi9, plate lit and pin E75 out of contact with tap sleeve H8 allowing the sleeve to move to collapsed or non-threading position.

The leadscrew nut mechanism is contained in the lower central portion of the arch so and is illustrated in Figures 3, 6, '7 and 8. The halfnuts 2% are formed internally with threads to mate with the external threads on leadscrew M8 and each is secured by screws 21% to one of a pair of bell cranks 2m, 22? Cranks Eli; and 2% are pivotally mounted by a pair of short shafts i222 and 22 respectively (Figure '7), both of which are journalled for rotation in the bottom wall of arch n; and also in suitable openings in the cover plate 226 which is secured to the wall oi arch it by screws 228,

An arm 23B of crank 253 is bifurcated and each division is provided with an opening to receive the pin 232 which is journalled therethrough. A link 23% connects pin 232 to another pin similarly mounted in an arm of crank. 225. Thus the pivotal movements of cranks 21s and 2251 to engage and disengage the half-nuts iii and leadscrew 148 are equal, opposite and simultaneous.

A bifurcated arm 233 of crank 22s supports the pin 2:10. Pin 24s is made easily removable for the replacement or the entire nut mechanism thus far described, as a unit when the leadscrew is to be changed for one of a different pitch. Between the divisions of arm 238 a link 2 12 is mounted on pin Edi? to connect the latter to a pin 2% which is journalled through one arm of a bell crank 24%. A stud its on which crank M6 is pivotally mounted is iournalled through the bottom of arch .5 and an opposed wall thereof. Stud 2 28 is provided with a large flanged portion 25s at the top thereof. Flanged portion 253 is provided with a plurality of arcuate slots 25! to receive the heads of screws 252 by means of which flange 25. 3 is secured to the wall of arch 46. Thus flange 2% may be secured in rotatably adjusted position. Since flange 250 is slightly eccentric with reference to the integral stud 248, such rotary adjustment of flange 250 has the effect of slightly shifting the center of stud 2M3 and varying the distance between the centers of pin 249 and stud 258, which distance must be closely adjusted to a value which prevents the arm of crank 2A5 and link 242 from lying in a straight line. This is necessary for the efficient functioning of the mechanism.

The other arm 25d of crank 24 i is also bifurcated and the two portions thereof extend on. opposite sides of a lead screw nut operating rod 256. An opening is provided in each portion of arm 254 to receive pins 258. Pins 25s are formed integrally with a pair of rectangular blocks 26!) which engage transverse grooves 262 formed in the Operating rod 255. From the above it should be apparent that a reciprocatmovement of rod. 255 will, through the con nections 2 32 and 23s with the crank its, cause the half-nuts 2M. alternately to engage with and disengage from the threads on leadscrew Me.

As seen in Figures 6 and 8, rod 256 is jour- 7 nal-led for reciprocation through bushings 2265 which are mounted in aligned openings in opposed walls of arch 36. Rod 255 is adapted to be moved am'ally in one direction by manual means. To enclose such means and the forwardly protruding end of rod 255 a housing 2% and cover plate 26%: are secured to the front of arch Q6 by screws 2'53 (Figure l). Journalled through the opposite sides of housing 256 is a shaft 222, through the enlarged, laterally protruding portion of which a lever 2'1 is passed for the manual rotation of said shaft.

Interiorly of housing 255 a lever 2% is secured upon shaft 272 by pin 218. Lever 275 is bifurcated to extend downwardly on opposite sides of the operating rod 253. Each side of lever 215 is provided with an opening to receive one of a pair of pins which are formed in' tegrally v ith rectangular blocks 282 (Figure 6). Blocks 2E2 engage opposed slots 28% in the rod 25%. It is therefore apparent that oscillating movement of hand lever in one direction will rotate shaft 2.52 and produce an axial movement of rod 256 to close the half-nuts 2K5 on leadscrew his.

A manually operable adjusing screw 28% is threadedly engaged in cover plate and abuts the forward end of rod 255 to provide the initial adjustment of the axial position of said rod. A look nut 23% is provided to retain screw 28% in adjusted position. A detent (Figure 8) is mounted in an opening 2232 formed in the wall of arch l6 and perpendicular to the axis of rod 255. A plug threaded. into the outer end of opening retains a spring in co1npression between said plug 29:3 and detent A recess 2% having an inclined surface on its forward side is formed on red adjacent detent Thus detent 253 by engaging the in clined surface of recess resiliently holds rod 259 in its forward position when the leadscrew nuts 2 i i are closed as shown Figure 6.

The rearward end. of rod 5% threadedly attached to the piston rod of a hydraulic cylinder As will be seen later, cylinder Elli is arranged to operate under pressure in one direction only, that is, it will move rod 253 rearwardly to open leadscrew nuts A twoway hydraulic pilot valve is secured by screws 3% to a plate Plate is mounted by bolts 3 38 to the bottom wall of arch 48 in such position that valve may be operated by the inclined surface are formed near the rear end of rod The purpose of valve 362 will he describe-cl later herein.

The chuck for holding the couplings for tapping and the mechanisms associated therewith are shown in Figures to 18 inclusive of the drawings. As best seen in Figures 12 and 13, the base of the machine is provided with a pair of parallel transverse channels 312 in which hardened ys Bi lare-secured by screws ME. A length of roller chain 323 rests upon each way 3M. A chuck carriage 328 has secured to the bottom thereof, by means of screws 322, a second pair of hardened ways 32!; by means of which said carriage 3% is supported upon the rollers of chain tit.

It will therefore be apparent that carriage 3-28 is capable of movement transversely of the machine. A depending flange portion 326 of carriage 3223 at the forward end thereof has a .pair of set screws 32:; threadedly engaged therein which abut the forward end of base iii to adiustably limit the movement of carriage 32b in one direction. Locknuts are retain screws 3.28 in adjusted position. A pair of plates 332 are secured to the rear surface of carriage 32s by screws 335 (Figure '10). A set screw 335 is threadedly engaged in each plate 332 to abut the vertical surface 338 of base it and thereby adjustably limit the travel of carriage 32s in the forward direction. Locknuts $56 retain screws 336 in adjusted position. The chains Eli? are retained between ways 3h"; and by means pins 3 22 embedded in each of said ways near the ends thereof.

The foregoing construction is only for the purpose of support and friction-free motion. The following elements are provided to retain carriage 320 on base ill and to guide the movement of the former. Base to is provided with a pair of upwardly projecting guides 3% having internal guiding surfaces 3% and external guiding surfaces 348. Surfaces 34%; are engaged by the sides of flanges 3% formed integral with chuck carriage 3253. Surfaces 3% are engaged by a pair of plate 352 secured to the outward side surfaces of Carriage 32s by screws 35%. A pair of horizontal plates 3% are secured by screws 358 to the bottom surfaces of flange portions 359 to engage downwardly facing surfaces of guides 3M and thus to prevent carriage are from lifting or tilting.

Upwardly extending side portions 350 of ca riage 3223 provide a large rectangular opening in the interior of said carriage 325 in which the chuck is mounted. The chuck is, of course, arranged horizontally to hold the work pieces with their axes vertical, that is, parallel with the axis of the tap it is essential, in order to obtain a condition of perfect alignment be'tv" en tap and work and thus to cut a thread which will be coaxial with the exterior of the work, that the chuck be allowed to float. That is, a certain amount of lateral movement of the chuck must be provided for, in order for the chuck to align itself with the spindle when the work is engaged by the tap.

Therefore, the chuck mechanism comprises the yoke 36? which is mounted within portions 3st? of carriage 320 upon a plurality of thrust bearings 35 (Figure 15). Studs pass vertically through bearings 354 and yoke 35,2 and each stud 3% is provided with an enlarged head 33% at the top thereof. A second thrust bearing Bill is interposed between head 368 on each stud and the top surface of yoke 362. Stud 386 also passes downwardly through an op g 3 2 in carria 32s. A part of opening 3'52 is counterbored to receive the coil spring 3H which surrounds stud 35B and is retained in compression between the bottom of the counterbore in opening 3'52 and a washer 375 by a pair of locknuts 373 threaded ly engaged upon the lower end of stud a s. Thus, yoke 3'62 is not clamped rigidly upon the carriage 32 3 but is resiliently held between bearings 35% and 376 by stud head and the action of spring 3M. Excessive vertical movement of yoke 352 is prevented by the top plates are which are secured by screws 35-32 to the top surfaces of carriage portions see (Figures 10 and 15) and which extend inwardly to overlap a portion of yoke 352. Plates 3% also surround the stud heads 35!! to prevent lateral movement thereof.

Studs .366 are further provided with spaced flange portions 384 which closely engage the bores of the upper and lower races of bearings 310 and BM respectively, thus preventing lateral movement of said races. Lateral movement of yoke 362 and the inner races of bearings 364 and 310 which are closely fitted in openings in said yoke 352, is permitted by reason of the fact that the openings 3% in yoke 362 and the other races of bearings 36 i and 3m through which stud 3% passes are made considerably larger than said stud.

Referring to Figure 11, a hydraulic cylinder 3% is mounted in an upwardly projecting bracket 39% which is formed as an integral part of the base it. The piston rod of cylinder 388 extends forwardly and has a collar 392 retained thereon by the nut 39 i. Collar 392 is provided with the flange portions 3% and. 398 at the forward and rear ends thereof, respectively. Collar 392 passes through an open-end slot 4M! in a depending lug EM formed integraily with chuck carriage 328. It will be evident therefore, that the flanges 395 and which are located on opposite sides of lug $32 will, upon the activation of cylinder 388, alternately engage the sides of said lug to move carriage 320 transversely. As before described, the limits or such movement are determined by the engagement of screws 328 with the forward surface of base All and, in the opposite direction, by the engagement of screws 335 with the base surface 338. The length of collar 3512 between end flanges 396 and S98 is substantially greater than the thickness of the adjacent portion of lug e62, thus providing a lost-motion connection which permits carriage 3243 to float a limited amount in the transverse direction on chains 398.

As shown in Figures and 12, a key 404 is secured in a recess in the top surface of each side of yoke 362 by screws 5%. Each key 404 is received in a mating keyway 68 in the lower surface of plate 38!]. Thus, chuck yoke 362 is free to float in the direction perpendicular to the direction of float of the carriage 326. The amplitude of lateral movement of yoke 362 is adjustably controlled by means of the cone-pointed set screw diil which is threaded through one of the plates 3% (Figure 12) and which engages a conical recess 352 in the top surface of yoke 362. The adjusted clearance between the point of set screw 4m and the recess 452 determines the amount of movement possible. A lock nut M4 retains screw ilfil in adjusted position.

The yoke 362 is U-shaped and the open end thereof is closed by a member 415 which is secured to said yoke 362 by screws 413 (Figure 10). Yoke end member Mt is provided with a cylindrical recess 420 (Figure 11) in the bottom of which a spacer 422 is seated to support the outer race only of a combination thrust and radial ball bearing 624 which is also mounted in the recess 62b. The inner race of bearing 42 is journalled upon one end of a bushing 428, a flange portion 428 of which is also seated in recess 420.

The forward end of yoke 3&2 is provided with an opening 63% in which the anti-friction bearings as: are mounted. A shaft 435 is journalled for rotation in bearings 332 and said bearings are retained in opening by a flange portion 43E of shaft 33 inwardly of flange 436, shaft 13 i extends through. one end of a chuck body member 383 and is keyed thereto by a pin 440. At the rearward end thereof, chuck body 433 is supported upon the bushing 325 and is secured thereto by screws 2:12. It is therefore apparent that chuck body are is rotatably mounted on yoke 362 and within the space enclosed by said yoke and end member MB. The forward end of shaft 434 is received in an opening in a hub 44% to which it is secured by a pin M5. A manually-operated handle 448 is secured in a rectangular slot 459 in the forward end of hub 444 by means of screws 452 (Figure 10). Handle 44B constitutes the means whereby chuck body 433 is rotated.

As seen in Figure 10, the chuck body 538 is also made in the form of a hollow rectangle, the interior of which is occupied by a pair of grip jaws 45 i and. 456. Jaw 454 is rigidly attached to the forward end of body 438 by screws 458. Jaw 456 is secured by screws 163 to one end of a block i-S2 which, in turn is secured by a pair or" screws 46 to the forward end of the piston rod 365 of a hydraulic cylinder 158 (Figure 11). Cylinder 468 is mounted by means of screws 47%! to the rearward end of yoke end member 416. It will be noted that piston rod 465 passes through member H6 and bushing 428 and is concentric therewith. Therefore, one chuck jaw, 454, is stationary with respect to chuck body 433 while the other jaw, 456, is movable toward and from the center of said body 338 by means of the cylinder 468. i

The coupling W to be threaded is held in the center of chuck body 438 and between jaws 45 i and #356 by means of a plurality of hardened tooth members 412 here shown as four in number, two on each jaw. Each tooth member l'iZ is formed with a series of parallel v-shaped serrations tit on the back surface thereof which mate with similar serrations formed on a surface of the chuck jaw. These serrations are held in mesh by means of a clamp 376 which is mounted by means of a screw 4?? in a recess 3% in the chuck jaw. Square serrations 382 are formed on the oblique end of clamp 416 which mesh with similar grooves in the face of tooth number 472 to prevent the latter from moving vertically. A compression spring 43 3, seated in a counterbore in the chuck jaw and surrounding screw 4'18, urges clamp 4E8 outwardly to quickly disengage serrations 432 when screw dis is loosened. A stud A 36 and nut 48S prevent movement of the heel of clamp 47$ and keep serra tions 482 engaged when screw W8 is tightened. It will be evident that the tooth member 472 may be adjusted toward and from the center or" the chuck body 438 by means of serrations ll-4 so that the work W will be securely gripped and approximately centered in the chuck. It will be understood that the chuck jaws its and 456 are replaceable for different sizes of couplings to maintain the axes of such couplings coincidental with the center of the chuck.

The upper and lower sides of chuck body member 438 and a large portion of chuck jaws 54 and 456 are covered by plates 4% which are secured to said body member by screws 492. Plates 4% are provided for the purpose of protecting the face of the chuck from damage and for preventing the entry of chips and cuttings into the mechanism of the chuck, particularly in the vicinity of the moving jaw #56.

The chuck body ass is made rotatable as above described so that, when one end of the coupling has been tapped the entire chuck, with the coupling firmly gripped, may be rotated to present the opposite end of the coupling to the tap on substantially the same axis. Except during such rotation, the chuck should be fixed in a horizontal position to keep the axis of the coull pling exactly vertical. This is accomplished in the following manner.

At each side of its rotational axis, a rectangular recess 394 is formed in the rear surface of body member 538. As seen in Figure 14, a block 455 is secured in one side of each recess 59% by screws 4%. A second block 559 having an inclined surface opposed to the block 595 is secured in the opposite side of recess 39 5 by screws 5132.

A hydraulic cylinder 565 is secured by screws 566 to the rearward surface of end ll ember 515 and is located laterally adjacent the cylinder 458. A bushing 538 is attached by screw 5H) upon the forward end of the piston rod 555 of cylinder 50 i. Bushing 5% extends into a recess 512 in the rearward end of a locking bolt 5H3 and is retained therein by a member 5H: which loosely surrounds said piston rod rear-wardly of bushing 505 and threadedly engaged in recess 512. A set screw 523 is provided to engage the external threads of member 5E5 in a radial direction and thereby prevent any undesired movement thereof.

The cylindrical lock bolt 5ft is mounted for axial movement in a bushing which, in turn, is frictionally fitted in a bore 522 in end member M6 which bore is formed concentrically with cylinder 504. A cap screw 52fpasses through member M5, is threadedly engaged in a wall of bushing 520 and extends into a keyway 525 in lock belt 514 to prevent rotation of the latter. Lock bolt 5h, is formed with a wedge-shaped forward end portion 528 which is designed to enter the space between blocks 496 and 586. When in this position, lock bolt bid will hold chuck body 33 exactly horizontal. It will be apparent that the axial position of lock bolt 5% is determined by the activity of the cylinder 5135.

A lever operated two-way hydraulic valve 535 is mounted in base 48 as shown in Figure 18. The stem of valve 535 has mounted thereon an operating headspool 532 which is pivotally connected by pins 534 with one arm of a bell crank 53S. Crank 536 is pivotally mounted by means of pin 538 on a bracket 55!] which is secured to a vertical web 542 of base 49 by screws 5%. The other arm of crank 536 extends forwardly over the top of web 552 and has attached at the end thereof,

by means of a pin 5 35, a roller 558. A cam plate r 550 is secured by screws 552 to the inwardly facing surface of the right hand carriage guide plate 355 (Figure 12). As carriage 325 is moved rearwardly, the inclined surface 555 strikes roller 548, rotating crank 536 to move the piston of valve 530 toward the right as seen in Figure 18. When carriage 32b is moved forward, cam 555 will release roller 5% and the piston of valve 53% will move toward the left under the impetus of the spring contained therein. The purpose of actuating valve sea by the movement of carriage 320 will appear later herein.

It has been noted that the rearward limit of the travel of carriage 325 is such as to dispose the work piece in exact vertical alignment with tap 50 for the threading operation. The carriage is shown in this position in Figure 11. The forward limit of travel of carriage 320 is such as to dispose the work piece above and in exact vertical alignment with the center of a work locating plate 555. This position of carriage 325 is illustrated in Figure 12. The function of work locating plate 555 and its operating mechanism is manifold. At the conclusion of an operation upon both ends of a coupling, plate 555 supports the coupling after its release from the chuck, lifts the coupling to the top or" the chuck for easy removal, returns downwardly to rest at a position which will support the next unthreaded coupling at the required distance from the tap, and finally, moves downwardly out of the chuck to permit the carriage to move rearwardly.

The mechanism for performing the above functions is shown in Figures 11, 12, 16 and 1'7. In Figure 12, plate 555 is shown in locating position. That is, the plate 555 has been extended into the chuck to support a work piece W at the proper distance from tap 55. Plate 555 is mounted upon a flanged bushing 556 and is secured thereto by screws 555. A pin 56% is employed to key the bushing 556 to a vertical shaft 562 which is mounted for axial movement in a tubular memher 534. Member 56s is mounted aligned openings in a housing member 565. An integral. flange portion 558 of member 555 is provided and screws 519 secure said flange 55% to housing 556 which is, in turn, secured in a-suitable recess in the front of base by means of screws 5'12.

A series of rack teeth 574 are formed along one side of shaft 562. A portion of the wall of tubular member 564 is cut away to permit rack teeth 514 to be engaged by a spur gear 5'55. Gear 575 is formed integrally with a co-axial pinion 573 (Figure 11). Both gear 515 and pinion 578 are journalled on a stud shaft 585 which is mounted in the rear wall of housing 565 and is stationarily retained therein by a set screw 582, A cam 535 is secured by screws 586 to the forward surface of gear 575 and cam 584 together with gears 515 and 578 are retained on stud 535 by a collar 588 and locknut 580 which latter is threadedly engaged on the forward end of stud shaft 586.

Pinion 518 is in constant mesh with the rack teeth 592 formed along one side of a cylindrical bar 595. Bar 595 is disposed horizontally in a suitable bore in housing 566 and extends therefrom at one end (Figure 12). A. hydraulic cylinder 588 is mounted by means of screws 593 to base 46 and is so disposed that the piston rod 5% thereof may be threadedly engaged in the end of bar 594. A nut 692 prevents accidental disconnection of piston rod 565 and bar 595. It is therefore apparent that the reciprocation of the piston of cylinder 59% causes vertical reciprocatory movement of shaft 562 and locating plate 555.

The locating mechanism is controlled by a servo valve 505 which is mounted in base by means of screws 605. As is known in the art, the movement of a hydraulic cylinder connected to such a valve is controlled by the movement of a plunger shaft 508 while the cylinder movement is stopped by the movement of a sleeve shaft 559 which is mechanically connected to the cylinder. One example of this type of valve is described in Hydraulics as Applied to Machines, copyright 1941, by Henry Ford Trade School, Dearborn, Michigan. As shown in Figure 167 of this publication in the inward movement of plunger shaft 503 the valve piston is moved a proportional amount to control fluid flow and an internal spring is thereby placed under compression, which urges the sleeve shaft 615 outwardly. In this case, sleeve shaft 5H3 is connected by pin SIZ to link 51-4. A pin 5! B connects link M5 to one arm of a bell crank 6H3. Crank M8 is pivotally mounted on a pin 52!) which is disposed through a convenient portion 622 of housing 586. A key 824 seated in a recess in portion 522 and secured thereto by a screw 625 prevents rotation of pin aec vee 13 628. The second arm of crank (H8 is provided with a pin 628 on which a cam follower roller 63% is mounted. Roller 630 is disposed in cooperative relation to the spiral cam 58% mounted on shaft 589.

The plunger shaft 663 has pinned thereto a roller 632 which cooperates with a cam 634 to move'shaft 6633 axially. Cam 634 is pivotally mounted by means of pin 635 on one end of the housing of valve 604. A lever 638 is formed integrally with cam eat and is attached by pin 850 to a link 642. The opposite end of link B42 is connected by pin 64A to one end of a lever 646. Lever t lt is mounted on a shaft 643 and is attached thereto for unitary rotation by a pin 650 (Figure 16). Shaft 658 is journalled through a pair of aligned bushings 552, 65s frictionally mounted in base 46. Shaft 648 is provided with a flange portion 655 at its forward end to prevent axial movement of said shaft.

A circular plate 658 surrounds flange 656 and is disposed against the forward wall of base at where it is held in position by a clamping ring 555 which engages a flange 682 formed on the circumference of said plate. Ring $68 is secured to the wall of base so by screws 664. The forward end of flange 655 is provided with a keyway 666 to receive mating rectangular projections 668 formed on the side flanges of a bracket member are which is secured to the end of flange 656 by screws $12. Bracket Elli is of U-shaped construction and encloses a lever 674 which is intermediately fixed to a pin 6'56 journalled through opposite sides of bracket 616. A handle iiiB is inserted in an opening in one end of lever Gi l and is retained therein by a pin 680 for manual operation of said lever (Figure 17).

The rearward surface of lever 67 i below pivot 57% is provided with a projection 632 which is adapted to engage a radial slot 685 in the forward surface of plate 658. A spring 63% and detent 688 are disposed in an opening in lever 674. Detent 688 engages the forward wall of bracket 616 to compress spring 686 and thus urge projection 682 into slot 684 when the radial position of these elements coincide to permit their engagement.

It will be apparent that handle 618, lever 614, bracket 870 and shaft 648 are rotatable as a unit. A. fixed stop 6% is provided on the forward surface of ring 650 to limit rotation of lever 67% in the counter-clockwise direction as seen in Figure 12. A lug 692 having a set screw 69% threadedly engaged therein is also formed integrally with ring 650. adjustable stop to limit rotation of lever 6'14 in the clockwise direction. The stop 6%, as will be seen more fully hereinafter, defines the lowermost or rest position of work locating plate 555; the adjustable screw 69 i defines the uppermost limit of travel of plate 555; and the slot 684 in plate 558 defines the intermediate or work locating position of locating plate 555. It is therefore desirable that the position of slot tea relative to stop 5% be made adjustable. It will be evident that such adjustment may be made by rotating the plate 658 relative to ring 568. This may be done only when the screws 56% are loosened to permit free rotation of plate 658, after which screws (its may be retightened to retain plate 653 securely in adjusted position. A scale 6% is engraved on ring 6 36 and an index line 698 is provided on the adjacent portion of plate 653 to facilitate the above-described adjustment.

A two-way hydraulic valve flit is attached by The screw 694 therefore serves as an means of screws 102 to housing 566 adjacent member 564 (Figure 12). Valve Hill is operated by a lever I04 which is pivoted at one end to housing 5% by a screw 196 and through the opposite end of which a set screw 168 is threaded. The vertically disposed screw M98 is retained in adjusted position by a nut Ht. Directly above screw 108, a rod H2 is mounted in a portion of housing 568 and flange 558. A spring l is is disposed in an opening H5 to surround a portion of rod H2. Rod H2 is provided with a flange H8 which retains spring H in opening Hi5 and which also limits the axial movement of rod H2 in the upward direction by engaging the bottom surface of flange 5% of member Fifi-*2 through which rod H2 is movable. The upper end of rod H2 extends upwardly from flange so that when locating plate 555 is lowered, the flange of bushing 555 will depress said rod '2 i 2, compressing spring H8- and finally, moving lever ltd downwardly a short distance to operate valve file.

The above described work locating mechanism is enclosed by cover plates lie, ":22 and res which are affixed to the front of base All by screws E25 (Figure 1).

Additional elements of the control system are illustrated in Figures 19 to24 inclusive. The left side of gear box 48 (as seen in Figure l) is provided with a vertical rectangular groove 128 (Figure 23), in which a dovetail guide 538 is secured by screws 532. Guide T30 is engaged on opposite sides by inclined grooves in a cam member "its and a clamp member rae. Members its and lit are clamped in any desired position on guide 735 by screws E38 (Figure 22). Cam 1% is provided, near the bottom thereof, with an oblique camming surface rec which faces toward the front of the machine.

Below cam 73d and clamp 536, a second pair of elements comprising a cam M2 and clamp TM are mounted upon the same guide 13 3 by a screw H6. Cam "M2 is provided, near the top thereof with an oblique cainming surface H3 which faces in the direction opposite that of surface T 33 on cam 131. It should be apparent that earns 53% and M2 are independently adjustable vertically along guide 730. Such adjustment is made by loosening screws E38 and Wit, moving the cams and clamps to the desired position and retightening said screws.

The function of cams FM and N52 is that of operating a lever Z59 through a roller 152 which is secured to the end of said lever its by a pin I54 (Figure 19). Lever 550 is mounted upon a shaft 155 and is secured thereto by any conven tional means. The shaft 755 is journalled in a pair of shouldered bushings E58 and 766 which are mounted in the inner and outer walls, respectively, of the left hand column member 62. A collar F532 is secured upon shaft '55s by a pin Hi l and is disposed inwardly adjacent bushing 753 to prevent axial movement of the shaft 55% and the members carried thereby.

In the interior of column 32 a. lever is secured upon shaft 556 by means of a pin E68. The outer end of lever 56% is bifurcated to extend on opposite sides of a valve operating member l'i's which is threadedly engaged upon the stem of valve H2. A pair of pins Tit are pivotally fitted in the opposed arms of lever 56% and have formed integrally therewith rectangular blocks lit. Blocks H6 engage slots in opposite sides of mereber H0 to translate rotary motion of shaft 1 5% and lever 166 to axial movement of member We, thereby operating valve 712. To support valve i 112, studs 11 8 are threaded into the wall of column 42 and valve H2 is secured to said studs T18 by cap screws 18%. It should be noted that lever 759 is also provided with a handle ill! for manual operation of valve 112.

The right hand side of gear box 53 is also provided with a vertical rectangular slot E82 (Figure 2) in which a key formed on the rear surface of a cam element 734 is fitted. Cam 185 is secured to the side of gear box it! by screws 1% (Figure 24). Longitudinal slots 188 in cam F84, through which screws 136 pass, permit a limited amount of vertical adjustment of the cam T84. Cam its is formed with two projections 190 and I92, having oppositely facing oblique cam surfaces 19% and 19 respectively.

The function of cam surfaces 195 and 19%; is the operation of a lever l9$ (Figure 20) through a roller 85% which is attached to said lever 193 by a pin 592. 3% and is secured thereto by a pin tilt (Figure 21). The shaft 835 is journalled in a pair of shouldered bushings 888 and Bill which are mounted in the inner and outer walls, respectively, of the right hand column member 44. A collar 8:2 is afixed on shaft 804 inwardly adjacent bushing 808 by means of pin Bi l to prevent axial movement of shaft 89 and the elements supported thereby.

In the interior of column M a lever Slfi is secured upon shaft 8% by a pin 3E8. Lever Bit is bifurcated to extend on opposite sides of a valve operating member cm which is threaded on the stern of a hydraulic valve 822. Member 829 is formed with flange portions 82d on each end thereof. Flanges 82s are engaged by lever tie to translate rotary movement of shaft 894 and lever 316 into axial movement of the stem of valve 822. To support valve 822, studs 825 are threaded into the wall of column M and valve 822 is secured thereto by screws 828.

A handle 83% (Figure 21) is inserted in one side of lever 798 and is affixed thereto by a pin 832 for manual operation of valve 822. Lever 798 is further provided with a pair of upwardly projecting ears 234 and $335 which alternately engage a pin 83% mounted in the wall of column a l, to limit the rotation of lever 798 and shaft 80 3 in both directions. An adjacent vertical wall of column e l, perpendicular to the walls through which shaft 8th; is journalled, has formed therein a boss 849. A bushing 842, having a flange portion this is mounted in boss 8 39 and is secured thereto by screws 835. A detent 858 having a wedge-shaped point is mounted for axial sliding movement in bushing 3&2. Rotation of detent 848 is prevented by a pin 85% which is fitted in bushing 852 and projects therefrom into a slot 852 in detent 25%.

The rearward end of bushing M2 is closed by a plug 854 which is threadedly engaged therein. The detent 3&8 is substantially hollow to receive a coil spring 855 which is held in compression between detent 868 and plug 355 and consequently urges detent 848 outwardly toward lever 198. A pin 858, also having a wedge-shaped point is frictionally fitted in lever 193 and projects therefrom toward detent 8-38. It will be apparent that the camming action between the points of detent 3&8 and pin 858, together with the force of spring 856 will permit lever 198 to come to rest only in one of two positions, that is, with pin 853 above detent 8% or below the detent as shown in Figure 21. The importance of this mechanism will be more evident later.

Lever IE3 is mounted upon a shaft I Operation The hydraulic system for operating the machine is shown diagrammatically in Figure 25. Hydraulic fluid is drawn from a reservoir or tank 869 by a pump 8G2, and is delivered thereby into the main pressure line see. A relief valve 8&5 is installed in line 854 for the purpose of delivering the pump output directly to the tank see if the pressure in the line rises above the value for which said valve is set. A sequence valve 8&8 is next installed in line 865. l'he entire output of pump 82 passes through valve 353 until the pressure in line 88% rises above a predetermined value for which valve 368 is adjusted, whereupon the fluid is delivered into line 8763.

With the machine at rest, the work locating mechanism control handle Bit will be in the position shown in Figure l, with lever 51A in contact with stop 59.9. At the same time, chuck carriage 320 will be in its forward or loading position. With carriage 320 in this position, crank 53% is released and valve 533 is open. Fluid will then pass from line Sill through valve 53* line 872, check valve 8?, servo valve 6M and line Bit into the right hand end of cylinder 595. Thus rod 5% is held at the leftward limit of its stroke and shaft 562 (Figure 12) is held at its lowermost position. In this position, work locating plate operates to close valve 798 and pressure is conducted from line 8W through valve and line 873 to the left hand end of pilot operated valve 8%.

This setting of valve e ll'permits fluid from line tit to pass through valve 88%, line 882, combination hand and pilot operated valve 364, and line 855% to the rear end of cylinder 388. Thus chuck carriage 32% is held in its forward posi tion. Fluid passes from line 866 through a metering valve 888 which is used to regulate the pressure of the fluid passing through said valve 388 to a combination hand and pilot operated valve 598. Valve set should be set initially to deliver fluid through line 89?. and flow control valve 8% to the forward end of the chuck jaw cylinder 468, thereby holding the chuck jaws open and ready for the insertion of a work piece.

A combination hand and pilot operated valve 895 should initially be set to permit hydraulic fluid to flow from line 818 through valve 895 and line 393 to the rearward end of lock bolt cylinder 5%, thereby holding lock bolt 5M in engagement with the chuck and preventing its rotation. The hand and lever operated valve T12 is initially held by cam M2 in its central or closed position. As a result, fluid is trapped in cylinder I08 and no motion of gear box 48 is possible. Cam 742 is in operation only when the gear box 58 has reached its uppermost position as shown in Figures 1, 3 and 9.

The first step in the-operation of the machine is to bring the locating plate 555 upward until it is level with the top of the chuck so that a heavy coupling may be loaded thereon with ease. To accomplish this, handle $18 is moved in a clockwise direction until it is stopped by the screw 694 (Figure 12). This rotates cam 63d, forcing plunger shaft 568 into the servo valve 594. As a consequence, fluid is cut off from line 816 and is permitted to flow from line ills through valve 539, line 812, valve 31%, valve see and line 9M to the left end of cylinder 59%, to move rack bar 59d toward the right. Simultaneously, line 816 is connected through servo valve 604 to line 906 which leads back to the reservoir 8%.

As seen in Figure 12, movement of rack bar 594 toward the right causes pinion 518 and gear 516 and cam 554 to rotatein a clockwise direction. Rotation of gear '56 causes shaft 562 and locating plate 555 to move upwardly through the chuck. Due to the known characteristics of servo valve 694, sleeve shaft did is at this time being urged outwardly, being restricted by its connection to crank tie whose position is dictated by the position of cam 58 i. Rotation of cam 586, therefore, permits crank Bid to rock in a clockwise direction and sleeve shaft 555 is allowed to emerge from valve 654. Such axial motion of sleeve shaft 6H3 will continue until its amount is equal to the amount plunger shaft 55%! has been depressed. At this point, pressure to cylinder 595 will be out off by servo valve 5% and the mechanism will stop in the desired position.

It will be noted thct the rise of plate 555 releases lever 555, opening valve we to permit fluid to pass from line filo through valve Mill and line 9|2 to the ri ht hand end of valve 885, while the pressure in line 578 to the left hand end of valve 880 is simultaneously cut off. Thus the position of the plunger of valve 38!} is reversed to close the passage to line 882. Movement of chuck carriage 325 is thus prevented until plate 555 returns to its rest position. Obviously, movement of the carriage while the work plate protrudes into the chuck would damage the machine.

A coupling blank will now be placed upon the plate 555 and handle 618 is rotated in a counterclockwise direction until the projection 532 on lever B15 engages the slot 584. Thus cam 534 is rotated, allowing plunger shaft 688 to emerge from servo valve 554. This reverses the direction of flow in servo valve 654 so that fluid passes from line 815 through valve 53! line 872, valve 814, servo valve 654 and line 815 to the right hand end of cylinder 59%. Consequently rack bar 554 is moved laterally toward the left, moving the now loaded plate 555 downwardly. When the coupling W reaches the correct gripping position shown in Figure 12, cam 584 has rotated sufficiently to force sleeve shaft 5H5 into servo valve 504 a distance equal to the distance which plunger sheft 558 has previously emerged. At this point, the servo valve 594 is again closed and no more fluid is delivered to cylinder 596, stopping plate 555 in the correct location.

The next step is to close the chuck grips upon the work piece. This step is initiated by manually operating valve 895 so that fluid is permitted to pass from line 855 through pressure control valve 888, valve 88!] and line slit to the rearward end of cylinder 458 to move chuck jaw 456 towe rd the stationary chuck jaw .54 and grip the coupling W therebetween. Valve 88! is adjustable so that the gripping pressure may be regulated to suit the requirements of a particular size of coupling. The counterbalance valve 894 is provided. to control the flow from the for ward end of cylinder etc so that the advance of chunk jaw 6556 is not too violent. Further, valve 894 maintains a high pressure in lines 908 and 81!} to retain plate 555 in position while the coupling is being gripped.

Loading plate 555 is then lowered to its rest position, shown in Figure 11, by rotating handle 618 in the counterclockwise direction until lever 614 contacts the stop 598. By a repetition of the activity of servo valve 555 described above, plate 555 is lowered to the rest position.

Next, the valve 884 is manually operated to permit fluid to pass from line 815 through Valve rock crank 536, closing valve 53c and cutting off the pressure to servo valve 584. Therefore, while carriage 325 is in tapping position, no operation of the work locating mechanism is possible.

When carriage 320 has stopped, by means previously explained, to position the coupling in alignment with tap 59, the gear box 43 and tap 513 may be lowered to close proximity to the coupling to be tapped. This is accomplished by manually operating the lever 18!, which as above explained, operates valve H2. Fluid is then permitted to pass from line 815 through valve 112 and line 9M to the upper end of cylinder N18. The lower end of cylinder I58 is connected through line 355, valve 952, and valve 112 to the exhaust line 936. Gear box 58 and tsp 59 therefore move downwardly until cam Z34 operates lever 150 to center the plunger of valve 112. Since valve H2 is a closed center type valve, both lines etc and 9M are closed and the downward movement of the tap stops.

The leadscrew nuts 2; are engaged upon the leadscrew M8 by manual operation of the handle 2M. Outward movement of handle 2'54 rocks lever 215 in a counterclockwise direction, moving rod 255 forwardly. Thus, by means of the previously described linkage (Figure 6) from lever arm 254 to the cranks 2l8 and 225, leadscrew nuts 2 M are closed and the tap is thereby advanced at the proper rate to cut the desired end of cylinder H38 equivalent to that occupied by the piston rod in the lower end.

It should be noted that the operation of valve 302 by rod 255 as the leadscrew nuts are manually closed, opens said valve, permitting fluid to pass from line 8'!!! through valve 352 and line 922 to the right hand side of each of the valves 884, 8963 and 885. This prevents the manual operation of these valves and precludes the possibility of accidental release of the lock bolt 5M, opening of chuck jaw eat, or movement of chuck carriage 325 during the tapping operation.

, As the tapping. operation is concluded, the tap automatically collapses. The cam surface 794 of cam 784 is adjusted to operate lever 198 immediately after the collapse of the tap. The

resultant operation of valve 822 permits fluid to pass from line am through valve 822, line .924

and metering valve 926 into the forwardend of cylinder eon whereby rod 256 is drawn rearwardly This movement of draulic pressure on valves 884, 890 and 896 permitting their operation as necessary.

Lever E8! is then operated manually to permit fluid to pass from line 315 through valve 112 and line. con into the lower end of. cylinder I08. The upper end of cylinder His is connected.

throughline 9M and valve 112 to the exhaust line 9136. Consequently gear box 48 and tap 50 19 move upwardly. At the end of such movement, cam 114,2 operates lever l50oto center the piston of valve 172 and thus .close lines 900 and M4 to sto the rise of gear box 48 and tap 5B and to hold them in raised position. During the rise of gear box 48 the cam surface 195 of earn 184 has again closed valve 822 and opened the connection with exhaust line 906, so that no pressure exists in the leadscrew nut operating cylinder 359. The hydraulic fluid is exhausted from cylinder 350 through check valve 942, line 924, valve 822 andline fillilto the reservoir 86B. Fluid leaking past the piston into the opposite end of .thecylinder is returned to the reservoir through line 944.. The tap will be reset when the tap is lifted as previously described. In case of emergency,-during the threading operation, the feeding action of the lead screw may be instantly interrupted by operation of handle 83!].

Valve 896 is now manually operated to permit fluid to pass from line .810 through valve 396 and line 928 to the forward end of the ,lock'bolt 7 cylinder 594. Look bolt 5! is therefore with drawn from its seat and the chuck is free to ro tate. The rearward end of cylinder 504 is connected through line 89iiand valve 896 to exhaust line 906. The chuck may now be rotated 180 by means of handle 44.8 to. reverse the work end for end and bring the ,unthreaded end thereof into threading position. The chuck is then relocked by reversing the position of valve 896 to supply pressure to the rear end of cylinder 504 through line 898. Promo-this point, the operations of lowering the tap, engaging the leadserew-nuts, collapsing the tap, disengaging the leadscrew nuts and raising the tap, proceed exactly as above described, in order to thread the second end of the work piece.

After the gear box 48 and tap 50 are stopped at. the top of their stroke and the tap re-set for the second time, the valve 884 is manually operated to permit fluid to pass from line 810 through valve 889, line v882, valve 884 and line 8.85 to the rearward end of cylinder 388. The forward end of cylinder 3878 is connected through line 910 and valve 884 to exhaust line v906. Therefore chuck carriage 320 is moved forward, releasing crank 536 which opens valve 539 to permit fluid to enter the servo valve system.

The. loading plate .555 is then raised in the manner previously described to its intermediate or locating position. Valve 890 is operated to permit. fluid to pass from line 854, valve 888,

valve 899 line 892 and valve .894 to the forward and of. cylinder 468. The rearward end of cylinder 4.68 is. connected at the same time throughline 998 and valve 890 110 tank line 9.06. Cylinder 468 thusopens the chuck and coupling W is deposited on the. locating plate .555. The

plate 555v carrying coupling W may now be raised to the. level of the top. of the. chuck, Where the finished coupling. may .easily berernoved and replaced by an unthreaded coupling, after which the cycle may be repeated as before.

Operation of the spindle motor H2 may "be entirely conventional, a control panel930 being installed on column M for the control of this and other necessary motors of the machine, such as a lubrication pump-motor, etc. Speed h n lev rs 932,. 934 and. .clutch lever 936 are also provided for gear box 48. An electric switch 938 may be attached to. column 44 for. operation by a dog 94!] on the sideof gear box 58i Switch. 938 is installed in thespindle motor circuit. to-

open said circuit and stop motor HZ i (4 p 20 descends too far, due to. either the failure of the tap to collapse or the failure of the leadscrew nuts to disengage.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore .intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a metal working machine, a vertically reciprocating spindle carrying a work fashioning tool, a horizontally reciprocable carriage a work holding chuck mounted on said carriage for movement therewith from a work receiving position to a position in axial alignment with said spindle, hydraulically actuated means operatively connected with said carriage for moving the chuck to and from the latter position, saidchuckincludinga movable section hydraulically actuated means connected to said chuck section and operable to open and close said chuck, a manually operable fluid supply control means individual to each. of .said hydraulically actuated means, means rotatably driving said spindle, a lead screw rigidly connected to said spindle means releasably connectible with the lead screw thread to axially move the same and said spindle in onedirection and advance the tool to the Work, actuating means operatively connected to said last named means, and means hydraulically interconnected with each of said control means responsive to the operation of said actuating means to connect said. releasably means with the lead screw, to establish a hydraulic interlock between said individual control meansv and retain said work holding chuck in fixed closed .position and in aligned relation with the spindle during advancing movement of the tool.

2. A metal-working machine as defined in claim 1,v said actuating means including a member manually operable in one direction to connect said releasable means with the lead screw, hydraulically operated means connected with said member and means interconnected with said responsive means and operated by means moving with. the spindle to control operation of said member by said hydraulically operated means in the opposite direction and disconnect said releasable means from said. spindle to limit advancing movement of. the tool and to release the hydraulic interlock on said individual control means.

3.. A metal working machine as defined in claim 1, wherein said chuck is indexible about a horizontal axis, together with hydraulically actuated meansdirectly coacting with and locking the chuck in indexed position and a manually operable control means therefor, and a hydraulic interlocking connection. between said latter control means and said first named control means to prevent operation of the chuck locking means during advancing movement of the tool.

4. In a metal working machine, a vertically reciprocating spindle carrying a work fashioning tool, a work holding chuck, a lead screw rigidly connected with the spindle a nut releasably engageable with the lead screw to axially move the 

